A light emitting diode (LED) is a device including an n-type semiconductor layer, a p type semiconductor layer, and an active layer interposed between the n type and p type semiconductor layers. When a forward electric field is applied to the n type and p type semiconductor layers, electrons and holes may be injected into the active layer and re-combine in the active layer to emit light.
In addition, an LED may include a reflection layer according to the type of a chip. For example, a flip-chip type is characterized by emitting light through a substrate. Accordingly, after a semiconductor layer is formed on the substrate, a reflection layer formed of or includes a metal is introduced on the semiconductor layer or a current spreading layer, and light is reflected by the reflection layer. Also, a barrier layer is provided on the reflection layer. The barrier layer is provided to prevent diffusion of the metal forming the reflection layer.